@Override
protected void copyContainment(EReference eReference, EObject eObject, EObject copyEObject)
{
	if(!(eReference.getEType().getInstanceClass().equals(PackageImport.class)))
	{
		//Copy non PackageImports untouched
		super.copyContainment(eReference,eObject, copyEObject);
	}
	else
	{
		//Copy PackageImports that target library models but not other models
		/*
		PackageImport pi = (PackageImport)eObject.eGet(eReference);	        			
		if(pi.getImportedPackage().isModelLibrary())
		{
			//the PackageImport is to a library so copy it
			super.copyContainment(eReference,eObject, copyEObject);
		}
		*/
	}
} 

Copier copier = new Copier(true){

	@Override
	protected void copyContainment(EReference eReference, EObject eObject, EObject copyEObject)
	{
		if(eReference.getEReferenceType() != UMLPackage.Literals.PACKAGE_IMPORT)
		{
			// Copy non-PackageImports without modification
			super.copyContainment(eReference,eObject, copyEObject);
		}
		else 
		{
			//Check to see if a PackageImports is a <<ModelLibrary>> or not. <<ModelLibrary>> packages should be copied.
			Collection<?> packageImportRef = (Collection<?>) eObject.eGet(eReference);
			List<PackageImport> piModelLibraryList = new ArrayList<>(packageImportRef.size());
			
			// Collect all imports of model libraries
			for (Object next : packageImportRef) 
			{
				PackageImport pi = (PackageImport)next;
				if ((pi.getImportedPackage() != null) && pi.getImportedPackage().isModelLibrary()) 
				{
					//add model libraries to be copied 
					piModelLibraryList.add(pi);
				}
				//TODO:Working on this bit below	        				
				else if((pi.getImportedPackage() != null) && !pi.getImportedPackage().isModelLibrary())
				{
					//deep copy packages which are not model libraries
					org.eclipse.uml2.uml.Package p = pi.getImportedPackage();
					List<org.eclipse.uml2.uml.Package> piPackageList = new ArrayList<>();
					//add the new package and the existing ones to the list
					piPackageList.add(p);
					piPackageList.addAll(((org.eclipse.uml2.uml.Package) copyEObject).getNestedPackages());
					Copier piCopier = new Copier(true);
					
					//Collection<EObject> results2 = piCopier.copyAll(p.eResource().getContents());
					//Collection<EObject> results2 = piCopier.copyAll(p.allOwnedElements());
					//piCopier.copyReferences();
					//List list = new ArrayList(results2);	        					
					
					//TODO:Stereotypes on the copied package are lost!
					//TODO:If the original model has Packages which are not PackageImports then the copying
					//procedure doesn't work for the non model library packageimported models
					//i.e. only the original package models are shown
					ECollections.setEList(((org.eclipse.uml2.uml.Package) copyEObject).getNestedPackages(),
							(List<? extends org.eclipse.uml2.uml.Package>) piCopier.copyAll(piPackageList));
					piCopier.copyReferences();
				}    				
			}
			// Copy the imports into the copied package.
			ECollections.setEList(((org.eclipse.uml2.uml.Package) copyEObject).getPackageImports(),
				(List<? extends PackageImport>) copyAll(piModelLibraryList));
		}
	}            	
};